WASHINGTON — Two weeks ago in Pakistan, Central Intelligence Agency sharpshooters killed eight people suspected of being militants of the Taliban and Al Qaeda, and wounded two others in a compound that was said to be used for terrorist training.

Then, the job in North Waziristan done, the C.I.A. officers could head home from the agency’s Langley, Va., headquarters, facing only the hazards of the area’s famously snarled suburban traffic.

It was only the latest strike by the agency’s covert program to kill operatives of Al Qaeda, the Taliban and their allies using Hellfire missiles fired from Predator aircraft controlled from half a world away.

The White House has authorized an expansion of the C.I.A.’s drone program in Pakistan’s lawless tribal areas, officials said this week, to parallel the president’s decision, announced Tuesday, to send 30,000 more troops to Afghanistan.

American officials are talking with Pakistan about the possibility of striking in Baluchistan for the first time — a controversial move since it is outside the tribal areas — because that is where Afghan Taliban leaders are believed to hide.

By increasing covert pressure on Al Qaeda and its allies in Pakistan, while ground forces push back the Taliban’s advances in Afghanistan, American officials hope to eliminate any haven for militants in the region.

One of Washington’s worst-kept secrets, the drone program is quietly hailed by counterterrorism officials as a resounding success, eliminating key terrorists and throwing their operations into disarray.

But despite close cooperation from Pakistani intelligence, the program has generated public anger in Pakistan, and some counterinsurgency experts wonder whether it does more harm than good.

Assessments of the drone campaign have relied largely on sketchy reports in the Pakistani press, and some have estimated several hundred civilian casualties.

Saying that such numbers are wrong, one government official agreed to speak about the program on the condition of anonymity.

About 80 missile attacks from drones in less than two years have killed “more than 400” enemy fighters, the official said, offering a number lower than most estimates but in the same range.

His account of collateral damage, however, was strikingly lower than many unofficial counts:

“We believe the number of civilian casualties is just over 20, and those were people who were either at the side of major terrorists or were at facilities used by terrorists.”